Birth Control Pill and Cardio Health: Big Questions Linger

Four out of five American women have used oral contraceptives at some point in their lives since the birth control pill's introduction in the 1960s. But while this form of birth control has made life easier in many ways for women, big questions remain about its safety, especially among women at elevated risk of cardiovascular disease.

A study in the January 20 edition of the Journal of the American College of Cardiology spells out what we know about oral contraceptives' safety -- and how much remains unclear.

Frankly, I find it shocking. After close to half a century of the pill's use, those gaps in knowledge are huge, according to the study, conducted by specialists in women's heart disease at Cedars-Sinai Medical Center in Los Angeles.

From the study (the emphasis is mine):

A variety of basic animal and human data suggest that
contraceptive hormones have antiatherosclerotic effects;
however, relatively less is known regarding the impact on
thrombosis, vasomotion, and arrhythmogenesis, mechanis-
tic pathways that also contribute to cardiovascular risk and
beneﬁt. No carefully controlled trials with cardiovascular
disease end points exist to guide our practice regarding
hormonal contraception, which is used by over 80% of U.S.
women at some point in their lifetimes.

And this (again with my emphasis):

There are no cardiovascular data available for the newest
generation contraceptive hormone formulations, including
the progestins that lower blood pressure and body weight, as
well as the nonoral routes (transdermal and vaginal). While
these newer formulations might be expected to have an
overall lower risk, speciﬁc study is needed. Current guide-
lines indicate that, as with all medication, contraceptive
hormones should be selected and initiated by weighing risks
and beneﬁts for the individual patient.

Translation: various studies have shown that oral contraceptives may help prevent atherosclerosis, or hardening of the arteries. But we don't know much about oral contraceptives' effect on other aspects of cardiovascular health -- and we don't have any useful data telling us whether taking the birth control pill (the old-fashioned, high-estrogen kind or the newer, lower-dose and extended-cycle formulations) leads to cardiovascular disease.

C. Noel Bairey Merz, director of the Women's Heart Center and the Preventive and Rehabilitative Cardiac Center at the Cedars-Sinai Heart Institute and the study's senior author, responds:

The most likely explanation is that hormonal contraceptives were/are developed to prevent pregnancy and are safe and effective for that purpose. Long-term constant use starting as teenagers and ending with menopause was not anticipated, and because women were not felt to be at risk for heart disease so a small increase in risk related to use would be well tolerated. There are other gender politics reasons that may or may not be contributing. I have said that if this was a male contraceptive, we would know much more.

And yet women keep asking for and getting prescriptions for oral contraceptives. How many of us even know to ask our doctors whether it might hurt our hearts? And even if we have an inkling that oral contraceptives can, for instance, contribute to formation of potentially lethal blood clots, do we have enough information about that risk to effectively weigh it against its many benefits (which may include some cardiovascular protections and reduction of ovarian cancer risk along with the regulation of our menstrual periods and the obvious protection against unwanted pregnancy)?

If you are on some form of the pill (or contraceptive patch or ring), are you concerned about its potential effects on your cardiovascular system? And have you discussed those concerns with your physician?

I find it shocking how little about the possible negative effects of the pill are known by or shared with women - on the libido, on our intestinal flora, even on the reliability of physical attraction. I have posted on this on my blog:

This is probably a dumb question, but I've never understood why it is so dangerous for menopausal women to take supplemental estrogen, yet women in their teens through 40s are urged to take supplemental estrogen through the BCP. Is it a difference of quantity?

I don't know. There are hundreds of millions of people who do not have safe drinking water, women are being raped, men are being tortured, children are at risk of malaria, and we are supposed to be shocked that we don't know what if any effects on heart disease oral contraceptives have? For heaven's sake, take them if you need, and then compensate by eating sensibly and going for a long walk everyday. And yes, stop complaining!